The Institute of Human Virology Clinical Trials Unit (IHV-CTU) integrates five clinical research sites (CRS) four in the US (a Baltimore-Washington consortium) and one in Nigeria, West Africa that focus on four major research objectives: Drug Research and Development; Optimization of Clinical Management for adult, adolescent and pediatric populations; HIV Prevention; and Vaccine Research and Development. The IHVCTU leadership, PI, William A. Blattner, MD, Co-Pi Robert R. Redfield MD and Co-Pi John F. Farley MD direct specific research areas and articulate complementary strengths in a collaborative process guided by the IHV-CTU communication plan to implement trials of highest GCP standard. The IHV-Treatment CRS, [Site Leader (SL) Charles Davis MD], with a 4000 person clinic base, targets Drug development and Optimization of Clinical Management. The Chase Brexton CRS (SL Patrick McLeroth, MD) employs a community clinical base to undertake Optimization of Clinical Management research trials, as does the Whitman Walker CRS, whose SL is Philippe Chiliade, MD. The Project BRAVE CRS, (SL William A. Blattner MD) with deep roots in the Baltimore community, targets HIV vaccine research and development. The IHV Nigeria CRS, SL John F. Farley MD, exploits a substantial 10,000 plus PEPFAR (President's Emergency Program for AIDS Relief) treatment cohort, to undertake HIV prevention trials among HIV discordant couples at risk for HIV CRF_02 AG infection. The IHV-CTU harmonizes research practice through organizational structures and a communication plan that employs uniform standard operating procedures (SOP) across all CRS, and clinical management working groups that optimize research practice. An Executive Committee comprised of the PI and Co-Pi allocate and reallocate resources to adapt to emerging clinical trial priorities guided by the Investigators Committee that advance the most promising interventions by re-allocating CTU resources. CRS community engagement through community-active advisory boards (CAB) are linked through the IHV-CTU CAB to effect community education and recruitment that effectively engages underserved African American populations in trials research. Results of this clinical research impact the public health by advancing HIV treatment standards, developing a vaccine, and learning more effective approaches to HIV prevention. ADMINISTRATIVE COMPONENT: